During normal operation of a gas turbine engine, one of the main aerodynamic challenges involves the efficient discharge of the high momentum combustion gas flow exiting the last stage of the turbine. Although it may be aerodynamically beneficial to use a horizontal exhaust configuration, such an axial exhaust may be impractical due to the overall footprint implications. Given such, it is standard practice to use a vertical and side mounted exhaust stacks that radially turns the combustion gas flow from an axial turbine. Specifically, a radial diffuser may be used to direct the combustion gas flow in a radial direction. The radial diffuser generally includes a number of struts mounted onto an inner diffuser guide and enclosed by an outer diffuser guide. The radial diffuser converts the kinetic energy of the combustion gas flow exiting the last stage of the turbine into potential energy in the form of increased static pressure. Increasing the overall static pressure recovery tends to increase the overall performance and efficiency of the gas turbine engine.
There is thus a desire for an improved diffuser design and an improved exhaust system for use with a gas turbine engine. Such an improved diffuser and exhaust system may provide enhanced aerodynamic performance and efficiency while reducing the overall axial length of the gas turbine engine as a whole. In addition, improvements to aero performance of exhaust systems traditionally has been linked with lower noise emissions, hence similar results may be expected from a radial exhaust diffuser as compared to a conventional axial configuration.